New jersey governor chris christie announcing that after struggle with obesity he revealed he secretly had lap band stomach surgery at the urging of family and friends and jon karl is here with the latest. He says it has nothing to do with the possible presidential run but will fuel that speculation. It sure will. If you talk to many so of his most fervent supporters who talked about him running are to president they will say he's privately concerned about his weight. He says it's bigger than 2016. That this was about his family. When he turned 50 last september he looked in the mirror. He realized he had to get healthier, that he was getting older and decided to do this surgery. Now, george, incredible secrecy around this. Christie checked into the hospital over presidents' day weekend under a pseudonym and told no one besides his family and chief of staff. Even the rest of his staff didn't find out he did this until yesterday. He said it's starting to work and does appear a bit slimmer. We saw him at the without correspondents' dinner. Didn't see any major change but look two pictures. They say he's lost about 30 pounds and looks like he pr has. We'll keep an eye out. Jon, thanks very much.

This transcript has been automatically generated and may not be 100% accurate.

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